In conventional automotive vehicle assembly lines as typically disclosed in U.S. Pat. No. 4,683,651, vehicle components are fed to a main assembly line after being subassembled by subassembly lines located outside the main assembly line. The main assembly line includes an automated assembly zone for installing the components via automatic machines and a manual assembly zone for installing the components via human labor downstream of the automated assembly zone, and each vehicle thus assembled is then subjected to inspection at the terminal of the main assembly line.
Namely, according to the conventional automotive vehicle assembly lines, appearance and functionality of each assembled vehicle are examined in an inspection process only after a plurality of assemble processes or zones, and when any improper assembly is identified in the assembled vehicle, the improperly assembled vehicle is normally taken out of the assembly line to be delivered to a common repair process, where the identified improper assembly is repaired to provide a complete assembled vehicle.
Further, with the recent development of vehicle-assembly-information sharing systems based on a computer network, a more sophisticated automotive vehicle assembly line has been proposed, which employs data input and display devices, based on a computer or the like, in inspection and repair processes. In this case, all identified improper assembly occurrences for a vehicle are entered via the data input device by a human operator in charge of the inspection process and the entered improper assembly occurrences are visually displayed on the computer display in the repair process so that the repair process can promptly repair the improperly assembled assemblies on the basis of the displayed occurrence information.
However, because the appearance and functionality inspection is performed in an assembled-vehicle inspection department located after the assembly line and identified improperly assembled assemblies are repaired in a common repair process outside the assembly line (i.e., out-of-line repair process), the conventionally-known automotive vehicle assembly lines would impose enormous loads on the common out-of-line repair process in situations where a great number of occurrences, particularly those occurring at initial assembly stages, are found in the appearance and functionality inspection.
Further, where there are many repair items per identified improper assembly, amounts of information to be fed from the repair process to the production-related departments become enormous, which would unavoidably lead to time delays in dealing with the improperly assembled assemblies.
It is therefore an object of the present invention to provide an automotive vehicle assembly line which readily achieves effective mutual assistance between human operators deployed at various workstations along the assembly line and can promptly identify an improper assembly.